Cyclization by Catalytic Ruthenium Carbene Insertion into C sp 3H Bonds
作者:Fermín Cambeiro、Susana López、Jesús A. Varela、Carlos Saá
DOI:10.1002/anie.201107344
日期:2012.1.16
A novel tandem Ru‐catalyzed carbene addition to terminal alkynes/insertion into CHbonds in alkynyl acetals, ethers, and amines has been accomplished under mild reaction conditions (see scheme; TMS=trimethylsilyl). This cascade provides an efficient approach to form complex spiro and fused bicyclic structures by 1,5‐ and 1,6‐hydride shift/cyclization sequences from vinylcarbene Ru intermediates.
Combined InCl<sub>3</sub>- and Amine-Catalyzed Intramolecular Addition of α-Disubstituted Aldehydes onto Unactivated Alkynes
作者:Benjamin Montaignac、Maxime R. Vitale、Veronique Michelet、Virginie Ratovelomanana-Vidal
DOI:10.1021/ol100729t
日期:2010.6.4
The combination of enamine-type catalysis to the indium-catalyzed activation of alkynes allows the efficient preparation of functionalized cyclopentanes bearing a quaternary stereogenic center. A broad range of formylalkynyl derivatives has been prepared. The InCl3/(Cy)(i-Pr)NH system efficiently promotes the carbocyclization reaction of alpha-disubstituted aldehydes in good to excellent yields.